During thoracic surgery it is necessary to gain access to the operating field intercostally, that is between the ribs of the patient. For open surgery a large incision is made and the operation is performed using clamps to pry the ribs apart, wherein it is not uncommon that the ribs break under the influence of such a spreading technique.
An alternative to the classic open surgery technique is minimal invasive thoracic endoscopy (thoracocscopy), for which a multiplicity of small access points are created between the ribs through which the endoscopic instruments can be guided into the operating field. However, the freedom of movement for the individual instruments is very limited due to the small clearances existing within the intercostal space.
A generic device for creating an intercostal transcutaneous access to an operating field is known from U.S. Pat. No. 5,776,110 with the aid of which the intercostal space can be widened. This known device has a base body in the form of an oval flange to which a cylindrical sleeve to be inserted into an incision is attached in a distal direction, the diameter of which is greater than the intercostal space. Two opposing webs are formed on the distal end of the sleeve by means of flattenings on the sides of the sleeve by which the known device can be introduced into the intercostal space. The sleeve is turned about 90° over the oval base body to push the ribs apart, so that the distal webs touch the ribs and push these apart.
It is possible with this known device to increase the size of the intercostal space but it is disadvantageous that the sleeve always has to be turned through the full 90° due to its form and the arrangement of the webs, as a result the size of the intercostal space is not adjustable.